Hercules Chemical

Henkel Rearrangement of Benzoic Acid and Phthalic Anhydride. Henkel technology is based on the conversion of benzenecarboxyhc acids to their potassium salts. The salts are rearranged in the presence of carbon dioxide and a catalyst such as cadmium or zinc oxide to form dipotassium terephthalate, which is converted to terephthahc acid (59—61). Henkel technology is obsolete and is no longer practiced, but it was once commercialized by Teijin Hercules Chemical Co. and Kawasaki Kasei Chemicals Ltd. Both processes foUowed a route starting with oxidation of napthalene to phthahc anhydride. In the Teijin process, the phthaHc anhydride was converted sequentially to monopotassium and then dipotassium o-phthalate by aqueous recycle of monopotassium and dipotassium terephthalate (62). The dipotassium o-phthalate was recovered and isomerized in carbon dioxide at a pressure of 1000—5000 kPa ( 10 50 atm) and at 350—450°C. The product dipotassium terephthalate was dissolved in water and recycled as noted above. Production of monopotassium o-phthalate released terephthahc acid, which was filtered, dried, and stored (63,64). 

Hercules Chemical produced an acidic organic waste derived from the manufacture of dimethyl terphthalate, which is used in the production of synthetic liber. The average dissolved organic carbon concentration was about 7100 mg/L and included acetic acid, formic acid, p-toluic acid, formaldehyde, methanol, terphthalic acid, and benzoic acid. The pH ranged from 3.5 to 4.0. The waste also contained traces (less than 0.5 mg/L) of 11 other organic compounds, including dimethyl phthalate, a listed hazardous waste. 

Randomly - Crosslinked PDMS. The polydimethylsiloxane (PDMS) used to make random networks was obtained from General Electric. Membrane osmometry showed to be 430,000 g/g-mole. The polymer was mixed with various amounts of a free-radical crosslinking agent, dicumylperoxide (Di-Cup R, Hercules Chemical Co.). Samples were then pressed into sheets and crosslinking was effected by heating for 2 h at 150°C in a heated press. Mc values were calculated using equation 2, and are included in Table I. 

Before this is closed, three points can be made regarding nomenclature. Older literature uses alpha for the 2-position of the indole ring. Thus, alpha-methyltryptamine, in early literature, refers to the indole-2-methyl, not to a side-chain methyl derivative. Throughout TIHKAL, the numbers are devoted to the indole ring, and the alpha and beta terms to the side-chain. And the use of the letter N refers to the side-chain amino nitrogen atom. The pyrrole nitrogen is the indole position 1. And finally, I found in my old files a news announcement (dated March 25,1974) that Hercules Chemical Company intends to build abig DMT plant in the Southern United States, with an annual capacity of 800 million pounds a year. In the industrial world, DMT can also stand for dimethylterephthalate. 

Once dried, the samples were cured at 150 C for 2 hours and 138 MPa of pressure In a template that gave a final thickness of 25 pm. After curing, the samples were extracted with acetone for 48 hours to remove any low molecular weight degradation products, dried and stored In the painted desiccator. Dlcumyl peroxide was obtained from the Hercules Chemical Company and repreclpltated from an ethanol solution. The acetophenone and dlcun l alcohol were purchased from the Aldrich Chemical Company and used as received. 

Hercules Chemicals Singapore Pte. Ltd/Aqualon Div.. 200 Pandan Loop, 07-01 Pantech 21, Singapore, 128388, Singapore (Tet 6775 5366 FAX 6775 5433)... 

Chief Chemist, DIC-Hercules Chemicals, Inc. Laboratory, Ichihara, Japan. 

In the mid-1970s, Hercules Chemical Company introduced two polyol ester plasticizers, Hercoflex 600 and Hercoflex 707. These plasticizers were prepared by the esterification of pentaerythritol and dipentaerythritol with a mixture of short-chain acids, predominately C6 acid. Although a few PVC applications and patents were developed, because of high costs, they have met with limited commercial success in PVC, although the products continue to be sold into the elastomer market in both North America and in Europe. A PVC plasticizer based on the pentaerythritol ester prepared with predominately C5 acids plus lesser amounts of C7 and C9 acids was patented in 1995 [41] as a low smoke plasticizer. The pentaerythritol ester prepared from C5 acids [42] is now being promoted by the Perstorp Group as a new phthalate alternative under the product brand Pevalen. 

Hercules Chemical invented and filed the original patent for epichlorohydrin rubber in 1957. They later licensed this technology and patents to BF Goodrich Chemical Co., which later sold all their interest in epichlorohydrin rubber to Zeon Chemical... 

Aromatic monomer resins which are highly saturated and purified are light in color and have excellent heat, light and oxygen resistance. Some examples of these products are Kristalex and Piccotex resins (Hercules Chemicals). 

Drew Chemical Corporation (Ashland Chemical, Inc.) Exxon Chemical Company Hercules, Inc. 

Dipentaerythritol is sold by Perstorp AB and by Hercules (United States), ditrimethylolpropane by Perstorp AB both in relatively pure form. Tripentaerythritol is also available however, the purity is limited. Trimethylolethane is produced commercially by Alcolac (United States) and Mitsubishi Gas Chemicals (Japan). 

Hercules, Inc. Hopewell, Va. La Roche Chemicals 1939 OxyTech HC3 diaphragm 1,8... 

Most commercial processes produce polypropylene by a Hquid-phase slurry process. Hexane or heptane are the most commonly used diluents. However, there are a few examples in which Hquid propylene is used as the diluent. The leading companies involved in propylene processes are Amoco Chemicals (Standard OH, Indiana), El Paso (formerly Dart Industries), Exxon Chemical, Hercules, Hoechst, ICl, Mitsubishi Chemical Industries, Mitsubishi Petrochemical, Mitsui Petrochemical, Mitsui Toatsu, Montedison, Phillips Petroleum, SheU, Solvay, and Sumimoto Chemical. Eastman Kodak has developed and commercialized a Hquid-phase solution process. BASE has developed and commercialized a gas-phase process, and Amoco has developed a vapor-phase polymerization process that has been in commercial operation since early 1980. 

Rosin and its derivatives are economically the most important natural resins. Approximately 1150 x 10 metric tons of these materials are produced annually and sold throughout the world. The principal producers are the People s RepubHc of China (ca 40%) and the United States (ca 25%), followed by Russia. Most of the remainder is produced in Indonesia, Portugal, Finland, India, Bra2il, and Mexico. In 1996, the lowest grades of rosin were priced at 750/t. Most rosin is converted to its many derivatives to meet requirements for industrial appHcations. The principal producers of rosin derivatives are Ari2ona Chemical Company, Hercules Incorporated, Westvaco, Union Camp, and Georgia-Pacific. 

Arizona Chemical Georgia Pacific Hercules Union Camp Westvaco Total... 

Most of the surface sizes used in North America are modified styrene maleic anhydride (SMA) copolymers. Commercially available materials include Scripset (Monsanto/Hercules Inc.), Cypres (Cytec), Sursize (Akzo Nobel), MSA (Morton), NovaCote (Georgia Pacific), and HTl (Hopton Technologies). Styrene acrylate emulsions that are commonly used include Jetsize and Unibond (Akzo Nobel), Basoplast (BASF), and Cypres (Cytec). Other materials used as surface sizes include acrylonitrile acrylate copolymer (Basoplast, BASF), stearylated melamine resin (Sequapel, Sequa), polyurethane (Graphsize, Vining Chemicals), and diisobutylene maleic anhydride copolymers (Baysynthol, Bayer). 

NatrosoM) Hjdroyjethjlcellulose, Fhjsical and Chemical Froperties, Aqualon Co., a Hercules Incorporated Company, Wilmington, Del., 1987. 

Chemical and Fhjsical Froperties of Hercules Ethjlcellulose, Hercules Inc., Wilmington, Del., 1982. 

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